Quantitative Viral Serology
Most individuals (80%) who have contracted the coronavirus are asymptomatic or experience mild or moderate symptoms which subside in two to three weeks. For others (15%), especially adults over the age of 60yrs as well as individuals with other medical problems such as high blood pressure, obesity, diabetes or heart conditions, it can cause severe illness with 5% requiring ventilation.
Approximately 30% of individuals that are infected with COVID-19 will display no symptoms. They can, however, infect others similarly to those that have symptoms. So how can we identify them especially since there is no onset of symptoms. Virus testing may not be enough. IgG and IgM antibody testing may indicate not only if they have been infected, but if the IgM is elevated and the IgG is not detectable, the individual may still be contagious.

3-Identifying asymptomatic COVID-19 patients